These amino acids are connected together with peptide bonds, and a few such bonds linking together form a polypeptide chain. What this actually entails is that proteins are long chain-like structure, with amino acids being the main ingredient. Now we previously learnt that amino acids are the building blocks of proteins. It can be anticipated that tannin-immobilized composites will continuously draw attention from more and more researchers, and further promising applications of tannin composites will be explored.Proteins are what we call biological polymers (i.e. Finally, we conclude with some thoughts on the open challenges and future perspectives of tannin composites. Further, the application of tannin-immobilized composites in the biomedical (tissue engineering, wound healing, cancer therapy, and biosensors) and other (leather materials, environmental remediation, and functional food packaging) fields is highlighted.

In this review, initially we summarize the design strategy of tannin-immobilized composites, mainly concentrating on the choice of immobilized substrate ( e.g., natural polymers, synthetic polymers, and inorganic materials) as well as the binding interaction ( e.g., Mannich reaction, Schiff base reaction, graft copolymerization, oxidation coupling, electrostatic interaction, and hydrogen bonding) between them. This strategy can endow tannin-immobilized composites with efficient manufacturing properties, high strength, good stability, easy chelating/coordinating ability, excellent antibacterial property, biological compatibility, bioactivity, chemical/corrosion resistance, and strong adhesive performance, which significantly expand their application in various fields. Inspired by the design of composite materials, tannin-immobilized composites have emerged as promising and novel materials and combine or even surpass the advantages of each of their components. However, they fail to satisfy the requirements in some specific applications ( e.g., environmental remediation) on account of their water solubility, making their separation and regeneration difficult.

Tannins, which are natural plant polyphenols, are widely used in different fields, especially in biomedical applications due to their unique properties, including high abundance, low cost, structural diversity, protein precipitation, biocompatibility, and biodegradability.

Secondary structure of protein download